(CANCELLED) Mechanical and Civil Engineering Seminar

Particles originating from human activities have existed for millennia, e.g., smoke from combustion, but the recent development of industry and combustion-based engine transportation has increased anthropogenic particles pollution. At the same time, technological advancement has also changed the character of these particles, increasing the proportion of nanometer-sized particles --"nanoparticles"-- and expanding the variety of chemical compositions. Indeed, the manipulation of matter at the scale of atoms, "nanotechnology," is creating many new materials with characteristics not always easily predicted from current knowledge. In this talk we report on our latest work on carbon-based nanomaterials (both from combustion and synthetic sources) with the overall goal to further fundamental and quantitative understanding of their formation mechanisms and physicochemical properties as well as to assess their interactions with biological media. Atomistic simulations in conjunction with precise chemical and biophysical experiments are the distinguishing characteristics of this effort. As engineered nanomaterials, we will focus on carbonaceous quantum dots, which have recently emerged and ignited tremendous research interest. Their favorable characteristics include size- and wavelength-dependent luminescence, resistance to photobleaching, bio-conjugation, and functionalization to produce chiral nanostructures. Carbon-based quantum dots show promise in areas such optoelectronics, catalysis, bioanalysis and drug delivery.